1. Field of the Invention
The present invention relates, in general, to a filter housing assembly for refrigerators and, more particularly, to a filter housing assembly for refrigerators, which is capable of preventing water from leaking during the replacement of filter elements and supplying water to the various portions of the refrigerator while its upper filter housing is separated from its lower filter housing.
2. Description of the Prior Art
As well known to those skilled in the art, some refrigerators have water purifying filters in their interiors so as to supply purified water to the outside of the refrigerators or produce ice using the purified water.
Referring to FIG. 1, the construction of a conventional filter housing assembly is disclosed.
As illustrated in the drawing, such a conventional filter housing assembly comprises an upper filter housing 10 and a lower filter housing 20. The upper filter housing 10 is combined with the lower filter housing 20 at its lower portion. The lower filter housing 20 is provided with a filter element (not shown) in its interior.
An inlet 10a through which water is supplied from the outside is formed in a side of the upper filter housing 10, and an outlet 11 through which water is discharged from the filter housing assembly is formed in the opposite side of the upper filter housing 10. A cylindrical connecting part 16 that is inserted into the upper portion of the lower filter housing 20 is formed in the central portion of the upper filter housing 10.
An inflow passage 10b that connects the inlet 10a of the upper filter housing 10 to the upper portion of the lower filter housing 20 is formed in the interior of the upper filter housing 10. A valve assembly (a reference numeral not assigned) is positioned on the upper portion of the inflow passage 10b and serves to cut off water supply during the replacement of filter elements by selectively opening and shutting the inflow passage 10b. 
The valve assembly comprises a valve body 12, a spring 13 and an actuating member 14. The spring 13 is fitted into the recess 12a of the valve body 12 at its upper portion and into the hole 14b of the actuating member 14 at its lower portion. The bottom surface of the actuating member 14 is rounded off so as to be easily moved on the cam surface (will be described) of the top of the lower filter housing 20. The actuating member 14 is moved upward and downward by the rotation of the cam surface of the lower filter housing 20, and, consequently, the valve body 12 is moved upward and downward.
An engaging projection 18 is formed on the bottom of the upper filter housing 10 so as to engage the upper filter housing 10 with the lower filter housing 20.
The lower filter housing 20 serves to guide water, which enters the filter housing assembly through the upper filter housing 10, so as to pass through the filter element. A through hole 20a into which the cylindrical connecting part 16a is fitted is formed on the upper portion of the lower filter housing 20, and a plurality of engaging projections 22 are formed along the side surface of the lower filter housing 20. The engaging projections 22 are engaged with the engaging projection 18 of the upper filter housing 10 and allow the filtering case 20 to be combined with the filtering housing 10 securely.
The operation of the conventional filter housing assembly is disclosed hereinafter.
When the lower filter housing 20 is rotated while the connecting part 16 of the upper filter housing 10 is fitted into the through hole 20a of the lower filter housing 20, the cam surface 20b of the lower filter housing 20 lifts up the actuating member 14 of the valve assembly that is inserted into the inflow passage 10b. As a consequence, the valve body 12 that is connected to the actuating member 14 through the spring 13 is moved up. When the valve body 12 is moved up, the inflow passage 10b is opened and, consequently, water can flow into the lower filter housing 20 through the inflow passage 10b. 
The water that is supplied to the upper filter housing 10 enters the lower filter housing 20 through one portion of the through hole 20a of the lower filter housing 20. The water is purified while passing through the filter element. Finally, the purified water is discharged through the other portion of the through hole 20a into the connecting part 16 of the upper filter housing 10. In such a case, the entering water and the purified water are not mixed because the connecting part 16 is deeply inserted into the through hole 20a. That is, the through hole 20a is partitioned by means of a portion 16a of the wall of the connecting part 16 and the filter element. The purified water discharged to the upper filter housing 10 is supplied to the ice-making unit of a freezer compartment (not shown), etc.
When the lower filter housing 20 is removed from the upper filter housing 10 by rotating the lower filter housing 20, the actuating member 14 is lowered down. As a consequence, the valve body 12 connected to the actuating member 14 through the spring 13 is lowered down, also. The lowered valve body 12 shuts the inflow passage 10b, and so cuts off the water supply.
The conventional filter housing assembly has the following defects.
That is, in accordance with the conventional filter housing assembly, upon the combination of the upper filter housing 10 and the lower filter housing 20, the inflow passage 10b of the upper filter housing 10 is opened. Therefore, while the actuating member 14 is moved upward by the cam surface 20b of the lower filter housing 20 before the upper filter housing 10 is combined with the lower filter housing 20 completely, the valve body 12 is moved up, and so the inflow passage 10b is opened. As a result, water that enters the filter housing assembly through the opened inflow passage 10b leaks through the small gap between the upper filter housing 10 and the lower filter housing 20. At this time, the water is spouted from the gap and leaks at a high pressure because the gap is small.
In addition, since the inflow passage 10b of the upper filter housing 10 is shut while the upper filter housing 10 is separated from the lower filter housing 20, water supply to the various portions of the refrigerator is completely cut off before the upper filter housing 10 is combined with the lower filter housing 20 again.
Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a filter housing assembly for refrigerators, which is capable of shutting the inflow passage of the filter housing assembly completely, thereby preventing water from leaking during the replacement of filter elements.
Another object of the present invention is to provide a filter housing assembly for refrigerators, which is capable of supplying water to the various portions of the refrigerator while its upper filter housing is separated from its lower filter housing.
In order to accomplish the above object, the present invention provides a filter housing assembly for refrigerators, comprising an upper filter housing having an inlet, an outlet, an inflow passage and an outflow passage; a lower filter housing being detachably combined with the upper filter housing and holding a filter element for purifying water supplied through the inflow passage of the upper filter housing; a valve having a first passage hole, a second passage hole and a third passage hole so as to selectively connect the inlet to the outlet, and the inlet and the outlet respectively to the first inflow passage and the first outflow passage; and a passage control lever fixedly connected at its one end to the valve so as to rotate the valve for the selective connection of the valve.
Preferably, the valve may comprise an upper valve member and a lower valve member in the form of circular plates, the second passage hole and the third passage hole being vertically and oppositely formed through both sides of the lower valve member, the first passage hole being horizontally formed through the upper valve member in a direction that passes a straight line, which connects the second passage hole with a third passage hole, at a right angle, and the passage control lever may be connected at its one end to a plane surface of the valve.
Preferably, the assembly may further comprise a valve-rotation preventing member for preventing the valve from being rotated while the upper filter housing is separated from the lower filter housing, the valve-rotation preventing member being positioned in a side of the upper filter housing.
Preferably, the assembly further may comprise a locking recess that is formed on a side of the upper surface of the lower valve member, the valve-rotation preventing member being inserted into the locking recess while the upper filter housing is separated from the lower filter housing and being removed from the locking recess while the upper filter housing is combined with the lower filter housing.
Preferably, the assembly may further comprise a filter-rotation preventing member for preventing the lower filter assembly from being rotated while water is supplied to the lower filter housing through the valve, the filter-rotation preventing member being at its upper end in contact with an inclined cam surface that is formed on a side of the bottom surface of the lower valve member.
Preferably, a filter-rotation preventing recess may be formed on the lower filter housing for receiving the lower end portion of the filter-rotation preventing member, the filter-rotation preventing member may comprise a body, a spring and a support, the body being in contact with the inclined cam surface and moved upward and downward by rotation of the inclined cam surface, the support being formed on the upper portion of the body and holding the spring, the spring elastically supporting the body and the support upward, and a supporting step is formed on the upper filter housing for supporting a lower end of the spring.
Preferably, the valve may comprise a cylindrical body, the first passage hole vertically formed in a central portion of the cylindrical body, and the second and third passage holes vertically and oppositely formed on both sides of the cylindrical body, and the passage control lever is connected at its one end to a plane surface of the valve.
Preferably, a stop portion is formed on an end of the passage control lever, and a lever-rotation preventing projection is formed on the outer surface of the lower filter housing for allowing a proper passage change to be performed and preventing the lower filter housing from being rotated by stopping the stop portion.
Preferably, the method may further comprise a lever locking plate for preventing the passage control lever from being rotated while the upper filter housing is separated from the lower filter housing, the lever locking plate surrounding the passage control lever.
Preferably, a locking neck may be formed on the passage control lever by cutting off a certain width of upper and lower portions out of the passage control lever at a predetermined position, and a locking hole having locking notch may be formed through the lever locking plate so that the locking neck is inserted into the locking notch portion of the locking hole in a case where the passage control lever is rotated at a predetermined angle.
Preferably, the method may further comprise a support projection for lifting up the lever locking plate when the upper filter housing is combined with the lower filter housing, the support projection being formed on the outer surface of the lower filter housing.